A variety of surfactants having emulsifying, dispersing, detergent, wetting, foaming and other properties have been used in various products including textile materials, rubber and plastic products, pesticides, metals, paints, pigments, construction materials and the like while utilizing such properties. Efforts have been made to obtain better acceptance of such products among end users by using a suitable surfactant. As a result of such activities, certain defects associated with the use of conventional surfactant have been revealed.
For instance, the use of certain surfactants is indispensable for the manufacture, stabilizing or workability of paints, printing inks, adhesives and the like. After these products have been used in painting, printing, bonding or other applications, not only is the presence of such surfactants not necessary but often adversely affects the water resistance, oil resistance or other properties of the resultant films or layers. As a countermeasure of these problems, various approaches have been studied including the reduction of the quantity of surfactant or the use of a surfactant having a large molecular weight. However, they are not compatible with the storage stability and/or workability of products to be imparted by the surfactant.
Surfactants are used in the emulsion or suspension polymerization of monomers for the production of water-based polymer emulsions or suspensions. Examples of surfactants which have been used for such applications include anionic surfactants such as alkyl sulfates, alkylbenzenesulfonates, dialkylsulfosuccinates and polyoxyalkylene alkyl (or aryl) ether sulfates; and nonionic surfactants such as polyoxyalkylene alkyl (or aryl) ethers, polyoxyethylenepolyoxypropylene block copolymers and polyoxyethylenesorbitan fatty acid esters. These surfactants may be used either singly or in combination. However, polymer emulsions and films formed therefrom including these conventional surfactants are far from complete satisfaction with respect to emulsion stabilities and film properties. Thus, many problems still remain unsolved including the polymerization, mechanical, chemical, freeze and storage stabilities and the pigment dispersing property of resultant polymer emulsions incorporating conventional emulsifiers. When films are formed from these polymer emulsions, the water resistance and adhesion thereof are often impaired by the presence of unbound surfactants in the films. When these emulsions are destroyed by means of, for example, salting out to recover polymer particles therefrom, a large amount of waste liquid containing the surfactant are necessarily formed as a by-product. For environmental reasons, this liquid must be subjected to expensive and complicated on-site water-treating processes before it can be disposed as effluent.
A number of patent documents disclose a novel type of surfactant which are polymerizable, degradable or otherwise reactive during or after use so as to be free from the foregoing defects. Examples of Japanese patent documents describing reactive anionic surfactants are listed as follows: Patent Application Nos. 46-12472, 46-34894, 49-46291, 56-29657, and Laid Open Application 51-30285, 54-14431, and 56-127697. Examples of Japanese patent documents describing reactive nonionic surfactants include Laid Open Applications Nos. 50-98484 and 56-28208.
U.S. Pat. No. 4,814,514 (Yokota et al.) discloses compounds prepared by the reaction of a glycidyl (meth)acrylate with a hydroxyalkylated polyalkyleneoxy fatty alcohol followed by reaction with an alkylene oxide and the use of these compounds as an emulsifier in the emulsion or dispersion polymerization of ethylenically unsaturated monomers.
U.S. Pat. No. 4,390,401 (Costanza) discloses the use of acrylate or methacrylate esters of polyalkylene oxide derivatives of alkyl/aryl phenols as wetting agents and adhesion promoters in ultraviolet curable systems. Compositions based on alkylene oxide derivatives may contain lower hydroxyalkyl compounds which can contribute measurably to the VOC (volatile organic compound) content of the composition.
A technical bulletin entitled "TREM LF-40: Reactive Anionic Surfactant for Emulsion Polymerization", Henkel Corporation, Ambler, Penn., states that TREM LF-40 is a sodium alkyl allyl sulfosuccinate with a reactive group in its molecule that will copolymerize with monomers via free radical polymerization. It is stated that the product, when used as a primary or secondary emulsifier, provides low foaming emulsions with improved water resistance.